Analysis of the Transient Characteristics of Grounding Fault Signals with Series Power Electronic Equipment

In order to solve the problem that how the series-type power electronic equipment affect the transient transition process of the faulty power systems under single-phase grounding fault, a 10kV small current grounding system model is built through MATLAB in this paper. An equivalent model of a series power electronic device using unified power flow controller (UPFC) is established. The UPFC will have varying degrees of influence on the transient duration, transient current and voltage amplitude, transient frequency and other electrical signals, when connected to the small current grounding system under single-phase grounding fault. It will further affect the sensitivity and reliability of the line selection method based on these transient electrical signals.